This invention relates to a method of manufacturing stator cores by winding magnetic strip into spirals.
After stator cores formed by winding a magnetic strip into spirals have been finally formed, the cores are generally subjected to the steps of winding coils thereon and machining the fitting portions thereof into end-flames of an alternator. However, due to working errors occurring upon stamping the magnetic strip, and variations in thickness locally developed on the magnetic strip itself, conventional methods of forming stators have resulted in an unsatisfactory accuracy concerning the inside diameter of the inner surface of stators formed of teeth and adapted to be opposite an associated rotor. Therefore, it is the existing state of the art that the inside diameter of such stators must be adjusted by suitable means, for example by finishing by a lathe. In addition, the conventional shaping methods have been disadvantageous in that, it is difficult to effectively shape stators because, upon spirally winding the magnetic strip, a rectangular cross section thereof changes to a trapezoidal cross section, resulting in unstable stacked or laminated structures.
It is an object of the present invention to provide a new improved method of economically manufacturing a stator core by spirally winding a magnetic strip which method produces a stable laminated structure to thereby render the forming of the structure effective while increasing the accuracy of the inside diameter of the core enough to eliminate the necessity of later adjusting the inside diameter.